TERF2IP
TERF2IP (TERF2 interacting protein), also known as RAP1, is a component of the shelterin complex that regulates telomere length and protection. It also acts as a transcription regulator and, in the cytoplasm, as a modulator of NF-kappa-B signalling. Browse Assay Genie's current range of TERF2IP research reagents below, or read on for the biology behind the target.
TERF2IP is a multifunctional protein that works both at chromosome ends and away from them. At telomeres it acts as a component of the shelterin complex (telosome), where it contributes to the regulation of telomere length and protection. Unlike other shelterin components, it is dispensable for telomere capping and does not take part in protecting telomeres against repair by non-homologous end-joining (NHEJ). Instead, it is required to negatively regulate telomere recombination and is essential for repressing homology-directed repair (HDR), a process that can alter telomere length.
TERF2IP does not bind DNA directly. It is recruited to telomeric double-stranded 5'-TTAGGG-3' repeats through its interaction with TERF2, a partner within the same complex. Independently of its telomeric role, it also acts as a transcription regulator: it is recruited to extratelomeric 5'-TTAGGG-3' sites through its association with TERF2 or other factors, and it regulates gene expression. The protein is found in the nucleus, in the cytoplasm and on chromosomes at telomeres. When cytoplasmic, it associates with the I-kappa-B-kinase (IKK) complex and regulates NF-kappa-B signalling by promoting IKK-mediated phosphorylation of RELA/p65, which leads to expression of NF-kappa-B target genes.
The TERF2IP gene encodes a member of the RAP1 family and is classed by HGNC in the shelterin complex gene group. The name reflects its identification as a TERF2-interacting protein, and RAP1 remains a common alias, as does the previous name telomeric repeat binding factor 2, interacting protein. Orthologues are annotated in both mouse and rat as Terf2ip.
TERF2IP helps regulate telomere length and protection as part of the shelterin complex, making it a key subject in studies of telomere maintenance.
It is dispensable for telomere capping but represses homology-directed repair and telomere recombination, which allows repair pathway choice at chromosome ends to be dissected.
Cytoplasmic TERF2IP associates with the IKK complex and promotes phosphorylation of RELA/p65, linking a telomeric protein to inflammatory gene expression.
TERF2IP is recruited to extratelomeric TTAGGG sites with TERF2 or other factors, so it is studied as a regulator of gene expression beyond telomeres.
TERF2IP regulates telomere length and protection as part of the shelterin complex, and it represses homology-directed repair and telomere recombination. It also regulates gene expression at extratelomeric sites and, in the cytoplasm, promotes NF-kappa-B signalling by supporting IKK-mediated phosphorylation of RELA/p65.
Yes. RAP1 is an alias for TERF2IP, and the UniProt name is telomeric repeat-binding factor 2-interacting protein 1. Take care not to confuse it with other proteins sharing the RAP1 abbreviation. It belongs to the RAP1 family, and HGNC places it in the shelterin complex gene group.
TERF2IP does not bind DNA directly. It is recruited to telomeric double-stranded 5'-TTAGGG-3' repeats through its interaction with TERF2. The same association, or other factors, can bring it to extratelomeric TTAGGG sites. Mouse and rat both carry a Terf2ip ortholog; check the datasheet of any product for its validated reactivity.
Other shelterin complex members, telomere-binding factors and NF-kappa-B pathway proteins with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q9NYB0; product specifications from Assay Genie datasheets.